Impregnated and coated sheet of fibrous material and process of producing the same.



UNIT

Tans an in.

' JOSEPH J. BYERS, OF BROOKLINE, MASSACHUSETTS, ASSIGNOR TO-PRODUCTS SYNDI- CATE, INC., OF BOSTON, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

IMPREGNATED AND COATED SHEET 0F FIBROUS MATERIAL AND PROCESS PRODUC- ING THE SAME. 4

No Drawing.

To all whom izf-mazy concern:

Be it known that I, JOSEPH J. BYERS, a citizen of the United States, and a resident of Brookline, county of Norfolk, Commonwealth of Massachusetts, (whose post-oilice address is 26 Broad street, Boston Massachusetts), have invented Improvements in Impregnated and Coated Sheets of Fibrous Material and Processes of Producing the Same, of which the following description is a specification.

This invention relates to-products obtained by the treatment of certain materials with cellulose derivatives, and more particularly normally permeable'or penetrable materials, especially of a fibrous nature such, for ex ample, as textile fabrics or leather, the object being to impart to such products certain desirable qualities. The invention further relates to the process for obtaining such products.

Leather or other fibrous materials, for example, treated by my process, are adapted to receive a variety of finishes of a very high quality and of a very durable and Wearresisting nature. This is due, among other things, to the fact that the finish is intimately united to and forms, so to speak, an integral part of the material with which the leather or other fibrous material or fabric has previously been impregnated in accordance with my novel process, so that the finish constitutes, one may say, a part of the leather or other fibrous materialto Which it is ap plied, as contrasted with an adherent coating or surface layer. As a result, when in use, the leather or other fibrous material, the material with which it is impregnated, and the finish thereof, all flex or move in unison, and there is no tendency of the finish to crack or separate from the material itself.

While this invention is applicable to a great variety of fabrics, it is particularly valuable in the production of leather having a variety of finishes, such as patent leather, gun metal leather and others.

The invention will be best understood from the following description of one illustrative product of my improved method, and of the best mode or manner known to me for practising such method, while its scope will Specification of Letters Patent.

Application filed April 18, 1917.

Patented Jan. 7, 1919.

Serial No. 163,081.

be more particularly pointed out in the appended claims.

In carrying out my process, the leather or other fibrous, porous or textile material, is preferably treated with a cement-like substance consisting of or including a cellulose derivative in solution and containing a quantity of non-oxidizing oil. This treat-.

ment is carried out in such manner as to impregnate the material throughout with the oil-containing, cement-like substance. This cement-like substance, containing a cellulose derivative and a n0n-oxidizing oil, will hereinafter be referred to briefly aS the cement.

The material composing the cement and the proportions in which they are mixed may be varied within wide limits. A suitable cement, for example, may be prepared by dissolving some cellulose derivative, a soluble nitro-cellulose such, for example, as nitrated cotton, in any suitable solvent, such by way of example, as acetone and alcohol in equal parts. If, for illustration, soluble nitro-cellulose and acetone and alcohol are used, one pound of soluble nitrocellulose to one gallon of solvent may be employed with good results, or a lesser proportion of nitrocellulose may be used ifgreater fluidity is desired. To this there is preferably added a substantial amount of some non-oxidizing or non-drying oil, preferably a vegetable oil. This, for example, may be castor oil in sufficient amount to impart such flexibility as may be required by the use to which the material is to be put. In the case of leather, for example, castor oil may. be added in the proportion of from four ounces to three pounds to each gallon of cement, depending upon the nature of the leather or skin to be treated.

The preferred method of impregnation is by immersing thematerial in a bath composed of the cement and heating the bath until the material is thoroughly impregnated. For illustration, a bath may be prepared of sufiicient volume and proportion to the mass of the material to be treated to maintain the material immersed for the required time thoroughly to impregnate it without impairing the fluidity of the bath or effectiveness of the treatment. The tank or other receptacle employed for the bath is preferably closed to prevent any substantial evaporation of the solvent during the treatment of the material and may also be provided with suitable controlled heating means so as to maintain the bath at a suitable temperature.

The temperature of the bath is preferably maintained at a point above the normal temperature of the air but below that which would cause rapid evaporation of the solvent or impair the material being treated. In the treatment of leather with a cement constituted as described, the temperature should be preferably less than 150 F. Good results are obtained between 125 and 130 F.

Porous materials, such as leather, usually hold absorbed more or less hygroscopic moisture. To facilitate the impregnation of the material with the cement, it is preferable to remove substantially all water'and hygroscopic moisture from the material before its treatment. This may be accomplished in any suitable or desirable manner, but in the case of leather, a simple method is to expose the material to a suitable drying temperature for a period of time long enough to drive out the moisture. The time and temperature required will differ for diflerent materials and for different masses of the same material. In the case of leather, for example, the leather may be hung or spread over night in a drying room or oven at a temperature of from 120 to 150 F. In the case of some textile fabric or thin sheet or web material, the same may be prepared for immersion by passing it slowly through a drying room or drying apparatus' The material should preferably be handled and the treatment carried out in a room where the air has a low humidity, so that in passing from the drying operation to the immersion, the material may have no'opportunity to absorb or collect any substantial or detrimental amount of moisture.

By the previous expulsion of substantially all the moisture in the material to be treated and immersing it while in a dry state, the permeation or impregnation of the material with the cement is facilitated, and it is possible to impregnate the entire mass therewith.

When dried as described, the material may be immediately plunged into a heated bath and there maintained for the length of time required thoroughly to impregnate it with the cement.

The period during which the immersion should be continued will vary with the ma.- terial and its thickness. In the case of leather, for example, several minutes to several hours may be required, according to the thickness of the leather. In the caseof some thin, permeable materials, a few minutes Furthermore, the water-repellent properties and flexibility are long continued, which I attribute to the fact that the oil which is contained in the cement and is sealed into the fibers or particles of the impregnated material by the cement cannot be washed out by exposure to moisture. When ordinary leather becomes Wet and is thereafter dried by exposure to heat, it loses its softness and flexibility, becomes dry and hard and cracks very readily. This is largely due to the fact that the oil, soap, grease or oil contained in the leather has been in part Washed out by the wetting of the leather and in part driven out by the subsequent application of heat for drying the leather. Leather which has been treated by my present method and which has become damp, can be readily dried by the application of heat without becoming hard or stiff and without losing its flexibility and water-repellent properties, which I also attribute to the fact that the oil is sealed into the individual fibers or particles by the cementand cannot be driven out by the heat used to dry the leather.

It will thus be seen that leather treated by my process appears to have an oil-flexed property which is substantially permanent, while the oil, commingled with the cement throughout the'body of the material, gives it a high degree of permanent flexibility and water-repellent property.

After the material has been impregnated in the heated bath and before being completely dried, it is preferably, though not necessarily, subjected to a condensing or compressing action which serves to press and bind the fibers more closely together and bet-' homogeneous mass leaving, as I believe, the oil sealed in the particles or fibers which are protected and incased or bound together by the cement throughout. This condensing action may be profitably performed when the drying of the impregnated material has been carried to a point sufficient only to set or ter unite the fibers and the cement into a harden the cement at the surface of the ma- I terial, the cement within the material being left sufficiently fluid to respond to the compacting action. This compacting action may be carried out by any suitable means as by pressure rolls or otherwise, but it may be I conveniently and effectively performed by resorting to direct pressure between two flat heated plates in a stationary press so con-' structed that the plates will exert a substantially uniform, continued pressure simultaneously on all parts of the material or a considerable area thereof for a more or less prolonged interval or until the cement is set.

Pressure is preferably yieldingly applied.

The impregnated material when compacted and dried possesses durability, toughness, flexibility and permanent water-repellent qualities to a high degree, and these qualities by this process may be imparted in the case of leather of relatively cheap or inferior grades, so as to make them available for uses and purposes not heretofore possible. I have found, moreover, that the permeation of the cement throughout the entire body of the sheet material lays the foundation not only for a great variety of surface finishes and for surface finishes of high luster, but for finishes which have a degree of permanence not heretofore obtained and which are unlike those ordinarily applied to cloth, leather or other sheet fabrics in that, being applied to the surface of the cement impregnated body anddissolved into or amalgamated with the thoroughly permeated cement, the surface finish becomes a part of the entire body of sheet material, itself bending or flexing and expanding or contracting as a part ofthat material which is in contrast to the behavior of a separate adherent coating such as the enamel coating in ordinary patent leather.

I will now describe the preferred mode and manner of imparting the finish to the impregnated material. Where the finished surface requires smoothness, as, for example, where it is desired to impart a dull or gun metal finish to split leather and particularly where the impregnated material has had its surface fibers laid and cemented down by the application of heat and pressure in the compacting operation, the surface of the material is preferably first finished by some suitable mechanical action, such as buffing, to giveit the required smoothness and evenness. In the case of split leather the impregnatedmaterial can be buffed to amuch smoother surface than before since the fibers are held to the surface by the cement and do not rough up under the action of the abrasive.

To the surface thus prepared a finishing cement is applied, the purpose of which is to amalgamate or unite with the body of cement with which the material is already,

impregnated. For this purpose a cement may be used similar to that used for the impregnation, but of varying degrees of fluidity, according to the finish desired andthe material being treated. S uch finishing cement, however, is usually thinner or more ing cement. For example, to finish a split' upper leather with a dull or gun metal surface a cement may be used employing approximately eight ounces of cellulose to a gallon of solvent. The amount of vegetable oil to be used in the finishing cement will depend upon the material, the finish desired, and the use to which the finished material is to be put. Generally the amount of oil in the finishing cement should be substantially less than in the case of the base or impregnating cement, the amount of oil in any case being kept down below the pointwhere it tends to leave the surface in a sticky or tacky condition. In some cases the finishing cement may be prepared Without oil. Coloring matter as desired may be added to the finishing cement according to the depth of color required, such coloring material being added to and mixed with the cement coating solution before the latter is applied. If desired a soluble coloring matter may be added to the cement with which the entire body is impregnated in the first instance, the coloring matter under suchcircumstances permeating the material throughout.

The finishing solution may be applied by any convenient mechanical means, preferably by spraying, although it may be applied by the brush method or a solution flowed on the material, the object being the production of a thin, evenly distributed surface film of a relatively fluid finishing cement which immediately uniteswith or dissolves into the thoroughly permeated cement body of the sheet material. The coated sheet is then preferably subjected to heat and pressure before the cement has hardened or set as by pressing it between heated rolls or fiat plates in order to give it the required sheen and finish.

This process of coating and pressing is repeated as many times as is necessary to obtain the desired finish. For example, in the case of leather to which it is desired to impart a gun metal finish, two coatings each followed by subjecting the material to heat and pressure will ordinarily suffice. A calf finish, which has more luster than gun metal finish, may usually be obtained, by way of further example, by applying a third still thinner coating without coloring matter, the

thinner coating being left without any su of various other grades of le th r, as, for example, patent leather may be had by applying one or more coatings of the thicker finishing cement containing oil, followed each by pressure under heated rolls or plates, and then applying one or more coats of the thin finishing cement, ordinarily without subsequent pressing.

For example, t obtain a satin finish on leather, the procedure employed in securing the calf finish may be employed and two thin finishing coats of the four ounce solution thereafter applied. For a patent leather finish three coats of the finishing solution, or four or even five may be required to obtain the desired brilliancy, the solution of nitro-cellulose for the finishing coats being preferably of the highest quality and filtered to eliminate any foreign particles.

These examples are merely illustrative, the number of finishing coatings, the haracter of the coatings as to fiuidity or the proportion of nitro-cellulose or the presence of oil or coloring matter in the cement coatings and the use or non-use of pressure and heat following any particular coating being all features as t which the widest latitude may be exercised, dependent on the charac ter of material, the nature of the finish and the inclination of the one employing the process. In fact, having obtained a thoroughly impregnated base, different methods of reaching a finish of substantially the same appearance may be followed by varying the number or ch aracter of the coatings and the action to which each coating is subjected, but whatever procedure is followed, the union between the surface finish and the thoroughly permeated cement is so complete that a maximum of permanency is secured for the finish. The process, furthermore, is applicable to a great variety of fabrics as well as various kinds of leathers, the exact method of treatment as to the application of successive finishing coatings necessarily varying with the material and the finish sought, V

This process is applicable to leather or other fabrics where the finishing coatings are employed to give a sheen or luster or any other desired appearance'to the surface of the material, and is also applicable where such coating or coatings are utilized to assist in altering the appearance of the material by some prearranged displacement of the surface fibers to give, for example, the appearance of embossing or graining. In em- 7 bossing split leathers, for example, the leather after being impregnated with the cement and one or more coats of the thicker finishing cement having been applied, it is then embossed in the ordinary way in the presence of heat, the heat giving the desired sheen. After the embossing has been done, one or more finishing coats of'the thinner coloring cement may be applied, as desired, for the purpose of adding luster to the'surface, such finishing coats being allowed to set preferably without the use of pressure. It has been found that leather or other fibrous material, and particularly split leathers, when impregnated and coated with the cement will hold the embossing much longer than if they are not so treated, owing to the fact that the fibers are firmly cemented and the heat employed in embossing sets them definitely and permanently in their new positions.

The finish produced by this process not only has high qualities of premanency with little or no tendency to crack, due to the uniformity of the material throughout, but whether in making a gun metal finish or calf finish or patent leather or any other finish, I have found that inferior grades of leather such as splits may be employed and the patent leather or other finished leather obtained by this process, when using such inferior leather, is superior in finish and durability of finish to that which has heretobefore been produced by the best methods when employing superior grades of leather, as, for example, grain leather. This is due, as I believe, to the fact that the finishing coating or coatings are united by the application of pressure and heat into one integral mass with the cement with which the material is impregnated so that the finish is a part and parcel, so to speak, of the impregnating material which ramifies throughout the leather or other sheet material and, under conditions of use, and temperature variations, etc., expands, contracts, flexes and bends as a part of that impregnating material and as a part of the sheet material to which the finish is applied. This eliminates the liability to crack or separate from the sheet material which is present in the case of an ordinary" adherent finishing coating, as in the case of ordinary patent leather, or as in the case of the ordinary pyroxylin finish appliedlmshgggni atggial.

In cases where chrome, tanned or other leather is employed which is permeated with a substantial amount of grease, the leather should preferably be" submitted to a degreasing process before impregnating the same with a cement. Any well known degreasing process may be employed, such, for example, as immersing the leather for the required length of time in a bath of naphtha or benzin or other cleansing'material. In the case of ordinary patent leather it is usual to degrease the leather prior to enameling it in order to make the enamel coating adhere. This degreasing operation robs the leather of much of its life. Where patent or other finish leather is produced by the process of the present invention, the grease or oil which is removed from the fibers and the interstices of the leather is replaced by the cement containing the oil with which the leather is impregnated, so that the leather base or sheet to which the patent leather or other finish is applied is of greatly superior quality as regards toughness, durability, strength and water-repellent qualities as compared with the original grease or oilfilled leather, instead of being inferior thereto as is the case with the patent leather heretofore employed.

In the case of textile fabrics, the latter should be free from sizing.

-While I'have herein described in considerable detail the referred mode of carrying out my improved process, it is to be understood that the precise steps may be varied more or less from the particular ones described while still following out the principles of this invention.

Claims:

1. The process of producing a surfacefinished fibrous material which consists in immersing the material while substantially free from moisture in a cement bath containing a cellulose derivative, a non-oxidizmg 011, and a suitable solvent, maintamlng said bath heated, keeping the material in,

said bath for a sufiicient time to cause the cement containing the oil to impregnate throughout the mass of the material, subjecting the impregnated material to pressure and heat before the cement has completely set to produce a homogeneous, compact, cementfilled body, applying in succession one or more surface films or coatings of cement also formed from a cellulose derivative in a suitable solvent, and causing said coatings to unite with the cement-filled structure, and subjecting the material after having applied thereto a finishing coating to heat and pressure to impart the desired luster or finish thereto.

2. The process of finishing sheet material which consists in immersing it in a heated bath having a cellulose derivative in solution together with a non-oxidizing oil, thor oughly impregnating the material with said solution, compacting and drying the impregnated material, applying a surface coating of a liquid having a cellulose derivative in solution, and subjecting the coated material to heat and pressure.

3. The process of finishing sheet material which consists in immersing it 'in a heated bath having a cellulose derivative in solution together with a' non-oxidizing oil, thoroughly impregnating the material with said solution, compacting and drying the impregnated material, applying a surface coating of a liquid having a cellulose derivative in solution, subjecting the coated ma- .terial to heat and pressure, and embossing the coated and impregnated material.

4. The process of producing surface fin mass of leather throughout with the oil and cement, buffing the surface of the impregnated leather, applying one or more surface films or coatings of a similar cement to the buffed material and causing the same to unite with the cement-filled leather, and heating and pressing the coated leather.

5. The process of producing a surface finished leather which consists in immersing the leather in a bath composed of a cellulose derivative in solution and a non-oxidizing oil, heating said bath thoroughly to impregnate the leather, compacting and drying the impregnated leather, applying one or more coatings of liquid having a cellulose derivative in solution, and finishing the coated surface.

6. As a new article of manufacture, a sheet of fibrous material impregnated throughout with a cement including a cellulose derivative and a non-oxidizing oil and compacted into a homogeneous cement-filled body and having a finished surface provided by a similar cement dissolved into and united with the surface of said cement impregnated material and forming an integral part of the cement-filled structure of the latter whereby the finished surface may bend or flex and behave as an integral part of the entire sheet.

7 As a new article of manufacture, a sheet of fibrous orpermeable material impregnated throughout with a cement which includes a cellulose derivative and a non-oxidizing oil to form a homogenous structure and a finished cement-coated surface permanently united to the cement-impregnated structure of the fibrous material to bend or flex and behave as an integral part of the entire sheet.

8. Asa new article of manufacture, a fibrous or permeable material impregnated throughout with a cement which includes a cellulose derivative and a non-oxidizing oil to form a homogeneous structure and an embossed cement-coated surface permanently united with the cement-impregnated structure of the fibrous material to bend or flex and behave as an integral part of the entire sheet.

9. As a new article of manufacture, a sheet of leather impregnated throughout with a cement including a cellulose derivative and a non-oxidizing oil and compacted into a homogeneous cement-filled body and having a finished surface provided by a similar cement including also a cellulose derivative dissolved into and united with the surface of said cement-impregnated leather and forming an integral part of the cement-filled rat lndl- 1,290,073

structureof the latter whereby the finished ment-coated surface permanently united 'to surface may bend, flex and behave as an in the cement-impregnated structure of the 10 tegral part of the entire sheet. leather, whereby the finished surface may 10. As a new article of manufacture, a bend or flex and behave as an integral part sheet of leather impregnated throughout thereof.

with a cement which includes a cellulose de- In testimony whereof, I have signed my rivative and a non-oxiding oil to form a name to this specification.

homogeneous structure, and a finished ce- JOSEPH J. BYERS. 

